On Tuesday, PCWorld published a new report in which it ran an exhaustive comparative benchmark among fourth-generation wireless carriers in the United States. In its “2012 Mobile Speed Test," the site came to discover that AT&T’s 4G LTE service features the fastest download speeds around, Verizon’s 4G LTE network provides the fastest upload speeds and T-Mobile's 3.5G HSPA+ network provides the fastest average download and upload speeds for its respective network technology.

Image source: PCWorld

In terms of its testing methodology, PCWorld ran a total of 177,000 "timed performance wireless bandwidth measurements" on AT&T, Sprint, T-Mobile and Verizon in 260 locations spread among 13 US cities of both urban and suburban environments. "We found some clear winners and losers, and some good news about wireless service in the United States as a whole." The first major discovery is that all four major wireless carriers, as a group (or should we say "as an oligopoly"), have increased their average download speeds for laptop-modem users by more than threefold, likely stemming from their urgent transition from 3G to 4G network technologies.

Image source: PCWorld

Image source: PCWorld

The report also discovered that AT&T's 3.5G HSPA+ network delivers 4G-like results, but the growth of the company's data speeds is slowing. More or less, the AT&T's speed increases over the past two years can be attributed to software upgrades and infrastructure improvements. "AT&T completed a networkwide upgrade to HSPA 7.2 technology in late 2009, then announced earlier this year that it had finished another upgrade to HSPA+ technology, which it says allows for maximum theoretical download speeds up to 14.4 mbps. AT&T also has been investing large amounts of capital in fiber-optic lines for the movement of cellular data to and from the core of its network.

PCWorld's full and comprehensive 4G network performance review for Q1 2012 can be found here.

While every other mobile hardware journalist around the world is ranting on and on about HTC's new EVO 4G LTE smartphone that will operate on Sprint's new Long-Term Evolution (LTE) network, we decided to pay homage instead to the first device that will actually see the light of day on said network, with consumer availability beginning sometime later this April. After all, the EVO 4G LTE won't be available until sometime towards the end of Q2 2012.

The smartphone in question is the LG Viper, which will officially become Sprint's first 4G LTE device. Sprint announced on Tuesday that pre-orders for the handset will officially begin Thursday, April 12, with the phone becoming available on an unspecified date later this month.

The smartphone will be priced at $99.99 after rebate and with a new 2-year agreement and should be able to take advantage of Sprint’s Everything data plan. The unlimited plan includes unlimited web, texting, and calling over the company's fourth-gen LTE network starting at $79.99 per month.

As many Apple consumers, enthusiasts, die-hards and mobile technology analysts have anticipated for months, the company's sixth-generation iPhone, launching Fall 2012, will most likely include a 4G LTE radio with support for Verizon and AT&T's fourth-generation networks in the United States, among support for many other LTE networks worldwide. While the hardware feature has only remained within the scope of a much-wanted rumor for the past few months, several codes of string in Apple's new iOS 5.1 firmware have offered empirical evidence suggesting that an LTE-enabled iPhone is indeed in the works at the company's Cupertino, Northern California headquarters.

Image source: iDownloadBlog

The folks over at iDownloadBlog ran through some Data Setting strings found deep within iOS 5.1 and have gathered screenshots of several strings reading:

- “4G_ON_CALL_WARNING_DISABLE” = “Disabling 4G will end your phone call. Are you sure you want to disable 4G?”- “4G_ON_FACETIME_4G_WARNING_DISABLE” = “Disabling 4G will end FaceTime. Are you sure you want to disable 4G?”- “4G_TEXT” = “Using 4G loads data faster, but may decrease battery life.”

For those willing to discover evidence at home, these iOS 5.1 files can be found within the following directory:

/System/Library/PreferenceBundles/MobileDataSettings.bundle/

The files are:

/DataSettings.plist

/English.lproj/DataSettings.strings

Image source: iDownloadBlog

As the discovery suggests, not only can iPhone users expect to be seeing 4G LTE support on future iterations of the device, but there is also the possibility of FaceTime video chat finally being supported over both 3G CDMA / HSPA+ and 4G LTE cellular connections.

At last, AT&T has released new information regarding its fourth-generation LTE network rollout plans for the United States with expanded coverage coming to 12 new markets beginning in April.

The markets in question include Staten Island, New York; New Orleans and Baton Rouge, Louisiana; St. Louis, Missouri; Cleveland, Canton and Akron Ohio; Naples, Florida; Bloomington, Lafayette and Muncie, Indiana; and Bryan-College Station, Texas. Unfortunately, this only puts the nation's second largest network at a total coverage population of 74 million Americans in 28 markets, compared to Verizon's total coverage population of 200 million Americans in 196 markets.

"AT&T customers in Cleveland, Ohio can look forward to even faster mobile Internet speeds very soon, on our leading lineup of smartphones and devices," said Larry Evans, vice president and general manager, AT&T Ohio and western Pennsylvania. "We're excited to bring Cleveland all that 4G LTE has to offer. Our teams will be working hard across the city toward our upcoming launch."